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Feat: Adds mapclear, mapgetkey, mapsetkey

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Feat: Error on undefined function

Fix: All ids are now prefix to prevent native var clashes.

Chore: __check helper function for ease of use
This commit is contained in:
Johan B.W. de Vries 2025-02-02 15:43:37 +01:00
parent 6055cddab2
commit 68e3c12d80
4 changed files with 309 additions and 101 deletions
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190
0-lang0py/lang0py.py
View File

@ -39,6 +39,36 @@ def skip():
PEEK = None PEEK = None
def __check(func, args: list[str], msg: list[str]) -> None:
result = func(*args)
if result:
return
sys.stderr.write('ERROR: ' + ' '.join(msg) + '\n')
sys.stderr.flush()
exit(1)
MAPSTORE = {}
def mapclear(mapname: str) -> str:
MAPSTORE.pop(mapname)
return ""
def mapgetkey(mapname: str, key: str, default: str) -> str:
return MAPSTORE.get(mapname, {}).get(key, default)
def mapsetkey(mapname: str, key: str, value: str) -> str:
MAPSTORE.setdefault(mapname, {})
MAPSTORE[mapname][key] = value
return ""
def registerid(id: str) -> str:
idname = mapgetkey("REGISTERID", id, "")
if idname:
return idname
idname = "id_" + id
return idname
def emitln(data): def emitln(data):
emit(data) emit(data)
emit(eol) emit(eol)
@ -81,12 +111,15 @@ def parseconststring():
emit(quote) emit(quote)
def parseexprvarref(): def parseexprvarref():
var = lexident() varname = lexident()
emit(var) varid = registerid(varname)
emit(varid)
def parseexprcall(): def parseexprcall():
funcname = lexident() funcname = lexident()
emit(funcname) __check(mapgetkey, ["FUNCREG", funcname, ""], ["Function", funcname, "does not exist"])
funcid = registerid(funcname)
emit(funcid)
emit('(') emit('(')
first = True first = True
@ -109,11 +142,12 @@ def parsestatdeclare(indent):
def parsestatset(indent): def parsestatset(indent):
skipchar(' ') skipchar(' ')
var = lexident() varname = lexident()
varid = registerid(varname)
skipchar(' ') skipchar(' ')
emit(' ' * indent) emit(' ' * indent)
emit(var) emit(varid)
emit(' = ') emit(' = ')
parseconststring() parseconststring()
@ -123,11 +157,12 @@ def parsestatset(indent):
def parsestatcalc(indent): def parsestatcalc(indent):
skipchar(' ') skipchar(' ')
var = lexident() varname = lexident()
varid = registerid(varname)
skipchar(' ') skipchar(' ')
emit(' ' * indent) emit(' ' * indent)
emit(var) emit(varid)
emit(' = ') emit(' = ')
parseexprcall() parseexprcall()
@ -174,11 +209,13 @@ def parsestatreturn(indent):
def parsestatcheck(indent): def parsestatcheck(indent):
skipchar(' ') skipchar(' ')
emit(' ' * indent) emit(' ' * indent)
emit('if not ') emit('__check(')
func_name = lexident() funcname = lexident()
emit(func_name) funcid = registerid(funcname)
emit('(') trace("funcid", funcid)
emit(funcid)
emit(', [')
notfirst = False notfirst = False
while True: while True:
@ -199,9 +236,7 @@ def parsestatcheck(indent):
skipchar(':') skipchar(':')
emitln('):') emit('], [')
emit(' ' * (indent + 1))
emit('sys.stderr.write(\' \'.join(["ERROR:", ')
notfirst = False notfirst = False
while True: while True:
@ -218,23 +253,21 @@ def parsestatcheck(indent):
if eol == peek(): if eol == peek():
break break
notfirst = True notfirst = True
emitln(']))')
emit(' ' * (indent + 1)) emitln('])')
emitln('sys.stderr.write(eol)')
emit(' ' * (indent + 1))
emitln('sys.exit(1)')
def parsestattrace(indent): def parsestattrace(indent):
skipchar(' ') skipchar(' ')
emit(' ' * indent) emit(' ' * indent)
emit('trace("') emit('__trace("')
var_name = lexident() varname = lexident()
varid = registerid(varname)
skipchar(eol) skipchar(eol)
emit(var_name) emit(varname)
emit('", ') emit('", ')
emit(var_name) emit(varid)
emitln(')') emitln(')')
def parsestat(indent): def parsestat(indent):
@ -277,8 +310,10 @@ def parsestat(indent):
parsestattrace(indent) parsestattrace(indent)
return return
funcid = registerid(call)
emit(' ' * indent) emit(' ' * indent)
emit(call) emit(funcid)
emit('(') emit('(')
first = True first = True
@ -315,19 +350,22 @@ def parseblock(indent):
def parsefunc(): def parsefunc():
funcname = lexident() funcname = lexident()
funcid = registerid(funcname)
mapsetkey("FUNCREG", funcname, "1")
trace('funcname', funcname) trace('funcname', funcname)
emit('def ') emit('def ')
emit(funcname) emit(funcid)
emit('(') emit('(')
first = True first = True
while ' ' == peek(): while ' ' == peek():
skip() skip()
var = lexident() varname = lexident()
varid = registerid(varname)
if not first: if not first:
emit(", ") emit(", ")
emit(var) emit(varid)
first = False first = False
if '/' == peek(): if '/' == peek():
@ -352,26 +390,26 @@ def emitheader():
emitln("import os") emitln("import os")
emitln("import sys") emitln("import sys")
emitln("") emitln("")
emitln("def eq(a: str, b: str) -> str:") emitln("def __eq(a: str, b: str) -> str:")
emitln(" return '1' if a == b else ''") emitln(" return '1' if a == b else ''")
emitln("") emitln("")
emitln("def lt(a: str, b: str) -> str:") emitln("def __lt(a: str, b: str) -> str:")
emitln(" return '1' if a < b else ''") emitln(" return '1' if a < b else ''")
emitln("") emitln("")
emitln("def add(a: str, b: str) -> str:") emitln("def __add(a: str, b: str) -> str:")
emitln(" return a + b") emitln(" return a + b")
emitln("") emitln("")
emitln("def emit(string):") emitln("def __emit(string):")
emitln(" sys.stdout.buffer.write(string.encode('latin_1'))") emitln(" sys.stdout.buffer.write(string.encode('latin_1'))")
emitln(" sys.stdout.flush()") emitln(" sys.stdout.flush()")
emitln("") emitln("")
emitln("def trace(header, value):") emitln("def __trace(header, value):")
emitln(" if os.environ.get('TRACE'):") emitln(" if os.environ.get('TRACE'):")
emitln(" sys.stderr.write(f'{header}={value!r}\\n')") emitln(" sys.stderr.write(f'{header}={value!r}\\n')")
emitln("") emitln("")
emitln("eof = chr(0xFF)") emitln("__EOF = chr(0xFF)")
emitln("eol = chr(10)") emitln("__EOL = chr(10)")
emitln("quote = chr(34)") emitln("__QUOTE = chr(34)")
emitln("") emitln("")
emitln("STDINCOLNO = 0") emitln("STDINCOLNO = 0")
emitln("STDINLINENO = 1") emitln("STDINLINENO = 1")
@ -379,41 +417,103 @@ def emitheader():
emitln("") emitln("")
emitln("def _readchar():") emitln("def _readchar():")
emitln(" char = sys.stdin.read(1)") emitln(" char = sys.stdin.read(1)")
emitln(" trace('char', char)") emitln(" __trace('char', char)")
emitln(" if not char:") emitln(" if not char:")
emitln(" return eof") emitln(" return __EOF")
emitln(" return char") emitln(" return char")
emitln("") emitln("")
emitln("def peek():") emitln("def __peek():")
emitln(" return STDINPEEK") emitln(" return STDINPEEK")
emitln("") emitln("")
emitln("def skip():") emitln("def __skip():")
emitln(" global STDINCOLNO") emitln(" global STDINCOLNO")
emitln(" global STDINLINENO") emitln(" global STDINLINENO")
emitln(" global STDINPEEK") emitln(" global STDINPEEK")
emitln(" if eol == STDINPEEK:") emitln(" if __EOL == STDINPEEK:")
emitln(" STDINLINENO += 1") emitln(" STDINLINENO += 1")
emitln(" STDINCOLNO = 0") emitln(" STDINCOLNO = 0")
emitln(" STDINCOLNO += 1") emitln(" STDINCOLNO += 1")
emitln(" STDINPEEK = _readchar()") emitln(" STDINPEEK = _readchar()")
emitln("") emitln("")
emitln("def stdinlineno():") emitln("def __stdinlineno():")
emitln(" global STDINLINENO") emitln(" global STDINLINENO")
emitln(" return str(STDINLINENO)") emitln(" return str(STDINLINENO)")
emitln("") emitln("")
emitln("def stdincolno():") emitln("def __stdincolno():")
emitln(" global STDINCOLNO") emitln(" global STDINCOLNO")
emitln(" return str(STDINCOLNO)") emitln(" return str(STDINCOLNO)")
emitln("") emitln("")
emitln("skip()") emitln("__skip()")
emitln("") emitln("")
emitln("MAPSTORE = {}")
emitln("")
emitln("def __mapclear(mapname: str) -> str:")
emitln(" MAPSTORE.pop(mapname)")
emitln(" return ''")
emitln("")
emitln("def __mapgetkey(mapname: str, key: str, default: str) -> str:")
emitln(" return MAPSTORE.get(mapname, {}).get(key, default)")
emitln("")
emitln("def __mapsetkey(mapname: str, key: str, value: str) -> str:")
emitln(" MAPSTORE.setdefault(mapname, {})")
emitln(" MAPSTORE[mapname][key] = value")
emitln(" return ''")
emitln("")
emitln("def __not(a: str) -> str:")
emitln(" if a:")
emitln(" return ''")
emitln(" return '1'")
emitln("")
emitln("def __check(func, args: list[str], msg: list[str]) -> None:")
emitln(" result = func(*args)")
emitln(" if result:")
emitln(" return")
emitln("")
emitln(" sys.stderr.write('ERROR: ' + ' '.join(msg) + '\\n')")
emitln(" sys.stderr.flush()")
emitln(" exit(1)")
def emitfooter(): def emitfooter():
emit("if __name__ == '__main__':\n") mainname = registerid("main")
emit(" main()\n") emitln("if __name__ == '__main__':")
emit(" ")
emit(mainname)
emitln("()")
def main(): def main():
emitheader() emitheader()
# Standard library constants
mapsetkey("REGISTERID", "eof", "__EOF")
mapsetkey("REGISTERID", "eol", "__EOL")
mapsetkey("REGISTERID", "quote", "__QUOTE")
# Standard library functions
mapsetkey("FUNCREG", "add", "1")
mapsetkey("REGISTERID", "add", "__add")
mapsetkey("FUNCREG", "emit", "1")
mapsetkey("REGISTERID", "emit", "__emit")
mapsetkey("FUNCREG", "eq", "1")
mapsetkey("REGISTERID", "eq", "__eq")
mapsetkey("FUNCREG", "lt", "1")
mapsetkey("REGISTERID", "lt", "__lt")
mapsetkey("FUNCREG", "not", "1")
mapsetkey("REGISTERID", "not", "__not")
mapsetkey("FUNCREG", "mapclear", "1")
mapsetkey("REGISTERID", "mapclear", "__mapclear")
mapsetkey("FUNCREG", "mapgetkey", "1")
mapsetkey("REGISTERID", "mapgetkey", "__mapgetkey")
mapsetkey("FUNCREG", "mapsetkey", "1")
mapsetkey("REGISTERID", "mapsetkey", "__mapsetkey")
mapsetkey("FUNCREG", "peek", "1")
mapsetkey("REGISTERID", "peek", "__peek")
mapsetkey("FUNCREG", "skip", "1")
mapsetkey("REGISTERID", "skip", "__skip")
mapsetkey("FUNCREG", "stdincolno", "1")
mapsetkey("REGISTERID", "stdincolno", "__stdincolno")
mapsetkey("FUNCREG", "stdinlineno", "1")
mapsetkey("REGISTERID", "stdinlineno", "__stdinlineno")
while True: while True:
if eof == peek(): if eof == peek():
break break

3
1-lang0py/Makefile
View File

@ -36,5 +36,8 @@ lang0py.py: lang0py.lang0 lang0py2.exe
mv $@.tmp $@ mv $@.tmp $@
-diff lang0py2.py lang0py.py -diff lang0py2.py lang0py.py
$(LANG0PY): $(CURDIR)/../0-lang0py/lang0py.py $(CURDIR)/../0-lang0py/lang0py.lang0
cd ../0-lang0py && make lang0py.exe
clean: clean:
rm -f lang0py*.py lang0py*.c lang0py*.o lang0py*.exe rm -f lang0py*.py lang0py*.c lang0py*.o lang0py*.exe

194
1-lang0py/lang0py.lang0
View File

@ -1,12 +1,14 @@
skipchar exp: registerid id:
declare act declare idname
declare lineno declare newidx
declare colno
calc act peek calc idname mapgetkey "REGISTERID" id ""
calc lineno stdinlineno if idname
calc colno stdincolno return idname
check eq exp act : "Unexpected character" act "expected" exp "at" lineno colno /
skip
calc idname add "id_" id
return idname
/ /
emitln data: emitln data:
@ -14,11 +16,6 @@ emitln data:
emit eol emit eol
/ /
increaseindent indent:
calc indent add indent " "
return indent
/
lexident: lexident:
declare word declare word
set word "" set word ""
@ -38,6 +35,22 @@ lexident:
return word return word
/ /
skipchar exp:
declare act
declare lineno
declare colno
calc act peek
calc lineno stdinlineno
calc colno stdincolno
check eq exp act : "Unexpected character" act "expected" exp "at" lineno colno
skip
/
increaseindent indent:
calc indent add indent " "
return indent
/
parseconststring: parseconststring:
skipchar quote skipchar quote
emit quote emit quote
@ -60,12 +73,15 @@ parseconststring:
parseexprvarref: parseexprvarref:
calc varname lexident calc varname lexident
emit varname calc varid registerid varname
emit varid
/ /
parseexprcall: parseexprcall:
calc funcname lexident calc funcname lexident
emit funcname calc funcid registerid funcname
check mapgetkey "FUNCREG" funcname "" : "Function" funcname "does not exist"
emit funcid
emit "(" emit "("
set first "1" set first "1"
forever forever
@ -97,16 +113,18 @@ parseexprcall:
parsestatdeclare indent: parsestatdeclare indent:
skipchar " " skipchar " "
calc var lexident calc varname lexident
calc varid registerid varname
skipchar eol skipchar eol
/ /
parsestatset indent: parsestatset indent:
skipchar " " skipchar " "
calc var lexident calc varname lexident
calc varid registerid varname
skipchar " " skipchar " "
emit indent emit indent
emit var emit varid
emit " = " emit " = "
parseconststring parseconststring
emit eol emit eol
@ -115,10 +133,11 @@ parsestatset indent:
parsestatcalc indent: parsestatcalc indent:
skipchar " " skipchar " "
calc var lexident calc varname lexident
calc varid registerid varname
skipchar " " skipchar " "
emit indent emit indent
emit var emit varid
emit " = " emit " = "
parseexprcall parseexprcall
emit eol emit eol
@ -188,11 +207,12 @@ parsestatcheck indent:
skipchar " " skipchar " "
emit indent emit indent
emit "if not " emit "__check("
calc funcname lexident calc funcname lexident
emit funcname calc funcid registerid funcname
emit "(" emit funcid
emit ", ["
set notfirst "" set notfirst ""
forever forever
@ -222,10 +242,7 @@ parsestatcheck indent:
skipchar ":" skipchar ":"
emitln "):" emit "], ["
calc indent increaseindent indent
emit indent
emit "sys.stderr.write(' '.join(['ERROR:', "
set notfirst "" set notfirst ""
@ -255,23 +272,20 @@ parsestatcheck indent:
set notfirst "1" set notfirst "1"
/ /
emitln "]))" emitln "])"
emit indent
emitln "sys.stderr.write(eol)"
emit indent
emitln "sys.exit(1)"
/ /
parsestattrace indent: parsestattrace indent:
emit indent emit indent
emit "trace(" emit "__trace("
emit quote emit quote
skipchar " " skipchar " "
calc varname lexident calc varname lexident
calc varid registerid varname
emit varname emit varname
emit quote emit quote
emit ", " emit ", "
emit varname emit varid
emitln ")" emitln ")"
skipchar eol skipchar eol
/ /
@ -324,8 +338,9 @@ parsestat indent:
parsestatcheck indent parsestatcheck indent
return return
/ /
calc callid registerid call
emit indent emit indent
emit call emit callid
emit "(" emit "("
set first "1" set first "1"
forever forever
@ -390,9 +405,11 @@ parseblock indent:
parsefunc: parsefunc:
calc funcname lexident calc funcname lexident
calc funcid registerid funcname
trace funcname trace funcname
mapsetkey "FUNCREG" funcname "1"
emit "def " emit "def "
emit funcname emit funcid
emit "(" emit "("
set isnotfirst "" set isnotfirst ""
forever forever
@ -403,11 +420,12 @@ parsefunc:
break break
/ /
skip skip
calc var lexident calc varname lexident
calc varid registerid varname
if isnotfirst if isnotfirst
emit ", " emit ", "
/ /
emit var emit varid
set isnotfirst "1" set isnotfirst "1"
/ /
calc char peek calc char peek
@ -431,26 +449,31 @@ emitheader:
emitln "import os" emitln "import os"
emitln "import sys" emitln "import sys"
emitln "" emitln ""
emitln "def eq(a: str, b: str) -> str:" emitln "def __eq(a: str, b: str) -> str:"
emitln " return '1' if a == b else ''" emitln " return '1' if a == b else ''"
emitln "" emitln ""
emitln "def lt(a: str, b: str) -> str:" emitln "def __lt(a: str, b: str) -> str:"
emitln " return '1' if a < b else ''" emitln " return '1' if a < b else ''"
emitln "" emitln ""
emitln "def add(a: str, b :str) -> str:" emitln "def __not(a: str) -> str:"
emitln " if a:"
emitln " return ''"
emitln " return '1'"
emitln ""
emitln "def __add(a: str, b :str) -> str:"
emitln " return a + b" emitln " return a + b"
emitln "" emitln ""
emitln "def emit(string):" emitln "def __emit(string):"
emitln " sys.stdout.buffer.write(string.encode('latin_1'))" emitln " sys.stdout.buffer.write(string.encode('latin_1'))"
emitln " sys.stdout.flush()" emitln " sys.stdout.flush()"
emitln "" emitln ""
emitln "def trace(header, value):" emitln "def __trace(header, value):"
emitln " if os.environ.get('TRACE'):" emitln " if os.environ.get('TRACE'):"
emitln " sys.stderr.write(f'{header}={value!r}\\n')" emitln " sys.stderr.write(f'{header}={value!r}\\n')"
emitln "" emitln ""
emitln "eof = chr(0xFF)" emitln "__EOF = chr(0xFF)"
emitln "eol = chr(10)" emitln "__EOL = chr(10)"
emitln "quote = chr(34)" emitln "__QUOTE = chr(34)"
emitln "" emitln ""
emitln "STDINCOLNO = 0" emitln "STDINCOLNO = 0"
emitln "STDINLINENO = 1" emitln "STDINLINENO = 1"
@ -458,43 +481,102 @@ emitheader:
emitln "" emitln ""
emitln "def _readchar():" emitln "def _readchar():"
emitln " char = sys.stdin.read(1)" emitln " char = sys.stdin.read(1)"
emitln " trace('char', char)" emitln " __trace('char', char)"
emitln " if not char:" emitln " if not char:"
emitln " return eof" emitln " return __EOF"
emitln " return char" emitln " return char"
emitln "" emitln ""
emitln "def peek():" emitln "def __peek():"
emitln " return STDINPEEK" emitln " return STDINPEEK"
emitln "" emitln ""
emitln "def skip():" emitln "def __skip():"
emitln " global STDINCOLNO" emitln " global STDINCOLNO"
emitln " global STDINLINENO" emitln " global STDINLINENO"
emitln " global STDINPEEK" emitln " global STDINPEEK"
emitln " if eol == STDINPEEK:" emitln " if __EOL == STDINPEEK:"
emitln " STDINLINENO += 1" emitln " STDINLINENO += 1"
emitln " STDINCOLNO = 0" emitln " STDINCOLNO = 0"
emitln " STDINCOLNO += 1" emitln " STDINCOLNO += 1"
emitln " STDINPEEK = _readchar()" emitln " STDINPEEK = _readchar()"
emitln "" emitln ""
emitln "def stdinlineno():" emitln "def __stdinlineno():"
emitln " global STDINLINENO" emitln " global STDINLINENO"
emitln " return str(STDINLINENO)" emitln " return str(STDINLINENO)"
emitln "" emitln ""
emitln "def stdincolno():" emitln "def __stdincolno():"
emitln " global STDINCOLNO" emitln " global STDINCOLNO"
emitln " return str(STDINCOLNO)" emitln " return str(STDINCOLNO)"
emitln "" emitln ""
emitln "skip()" emitln "__skip()"
emitln "" emitln ""
emitln ""
emitln "MAPSTORE = {}"
emitln ""
emitln "def __mapclear(mapname: str) -> str:"
emitln " MAPSTORE.pop(mapname)"
emitln " return ''"
emitln ""
emitln "def __mapgetkey(mapname: str, key: str, default: str) -> str:"
emitln " return MAPSTORE.get(mapname, {}).get(key, default)"
emitln ""
emitln "def __mapsetkey(mapname: str, key: str, value: str) -> str:"
emitln " MAPSTORE.setdefault(mapname, {})"
emitln " MAPSTORE[mapname][key] = value"
emitln " return ''"
emitln ""
emitln "def __check(func, args: list[str], msg: list[str]) -> None:"
emitln " result = func(*args)"
emitln " if result:"
emitln " return"
emitln ""
emitln " sys.stderr.write('ERROR: ' + ' '.join(msg) + '\\n')"
emitln " sys.stderr.flush()"
emitln " exit(1)"
/ /
emitfooter: emitfooter:
declare mainname
calc mainname registerid "main"
emitln "if __name__ == '__main__':" emitln "if __name__ == '__main__':"
emitln " main()" emit " "
emit mainname
emitln "()"
/ /
main: main:
emitheader emitheader
mapsetkey "REGISTERID" "eof" "__EOF"
mapsetkey "REGISTERID" "eol" "__EOL"
mapsetkey "REGISTERID" "quote" "__QUOTE"
mapsetkey "FUNCREG" "add" "1"
mapsetkey "REGISTERID" "add" "__add"
mapsetkey "FUNCREG" "emit" "1"
mapsetkey "REGISTERID" "emit" "__emit"
mapsetkey "FUNCREG" "eq" "1"
mapsetkey "REGISTERID" "eq" "__eq"
mapsetkey "FUNCREG" "lt" "1"
mapsetkey "REGISTERID" "lt" "__lt"
mapsetkey "FUNCREG" "not" "1"
mapsetkey "REGISTERID" "not" "__not"
mapsetkey "FUNCREG" "mapclear" "1"
mapsetkey "REGISTERID" "mapclear" "__mapclear"
mapsetkey "FUNCREG" "mapgetkey" "1"
mapsetkey "REGISTERID" "mapgetkey" "__mapgetkey"
mapsetkey "FUNCREG" "mapsetkey" "1"
mapsetkey "REGISTERID" "mapsetkey" "__mapsetkey"
mapsetkey "FUNCREG" "peek" "1"
mapsetkey "REGISTERID" "peek" "__peek"
mapsetkey "FUNCREG" "skip" "1"
mapsetkey "REGISTERID" "skip" "__skip"
mapsetkey "FUNCREG" "stdincolno" "1"
mapsetkey "REGISTERID" "stdincolno" "__stdincolno"
mapsetkey "FUNCREG" "stdinlineno" "1"
mapsetkey "REGISTERID" "stdinlineno" "__stdinlineno"
forever forever
calc char peek calc char peek
calc iseof eq char eof calc iseof eq char eof

23
README.md
View File

@ -155,6 +155,29 @@ Return true if the given strings are the same.
Return true if a would sort before b. Return true if a would sort before b.
#### mapclear mapname
Maps are global and can be used from any function.
Clears all values set in the map named `mapname`.
#### mapgetkey mapname key
Maps are global and can be used from any function.
Looks up `key` in the map named `mapname` and returns it.
If not found, returns an empty string.
#### mapsetkey mapname key value
Maps are global and can be used from any function.
Adds a mapping from `key` to `value` to the map named `mapname`.
#### not a
Returns "1" if a is empty; otherwise, returns "".
#### peek #### peek
Checks stdin for the next character and returns it. Checks stdin for the next character and returns it.